A case report of agranulocytosis caused by acute hepatitis B virus infection.

RATIONALE: Acute hepatitis B virus (HBV) infection is clinically characterized by hepatic inflammation and parenchymal injury. As a systemic viral infection, HBV can reduce peripheral blood cell counts via suppressing bone marrow hematopoiesis. Agranulocytosis is defined as severe neutropenia, with an absolute neutrophil count below 0.5 × 109/L. Standardized diagnostic and therapeutic protocols for HBV-associated agranulocytosis have not been established in clinical practice guidelines. Particularly, antiviral therapy in reversing HBV-induced bone marrow dysfunction remains to be fully elucidated. This case report aims to describe this clinical entity and elucidate the potential benefits of timely early antiviral intervention.

PATIENT CONCERNS: A 51-year-old female patient presented with unexplained fatigue persisting for over 20 days, coupled with anorexia and dysgeusia for greasy food.

DIAGNOSES: Acute HBV infection complicated with neutropenia, confirmed by follow-up comprehensive evaluations after the initial laboratory findings of marked elevation of liver enzymes and leukopenia.

INTERVENTIONS: The patient received liver protection therapy with phosphatidylcholine and magnesium isoglycyrrhizinate, as well as supportive care to stimulate leukocyte production. Due to persistent leukopenia and detectable elevation of HBV deoxyribonucleic acid, entecavir was initiated for antiviral treatment.

OUTCOMES: The above abnormal symptoms were relieved after antiviral therapy. Liver function and neutrophil counts returned to normal levels, and HBV deoxyribonucleic acid levels decreased significantly. Hepatitis B surface antigen seroconversion was achieved normal level after 6 months; therefore, clinical treatment was successfully discontinued. Follow-up showed sustained virologic and hematologic remission.

LESSONS: This case highlights acute HBV infection as a causative factor for severe neutropenia/agranulocytosis. Importantly, the study reveals that early antiviral treatment can not only suppress viral replication but also reverse bone marrow suppression, leading to complete hematologic recovery and functional cure (hepatitis B surface antigen seroconversion). This study demonstrates that antiviral therapy is necessary for the management of acute HBV with severe hematologic complications.